A surprise inspection has turned up serious safety violations that could have caused an explosion at another Massey Energy Co. coal mine in West Virginia, the federal Mine Safety and Health Administration said Thursday.

Inspectors caught Massey illegally cutting too deeply into the coal seam at its Seng Creek Powellton Mine about 40 miles south of Charleston in Boone County, the agency said. A foreman also admitted skipping mandatory tests for explosive gases, and inspectors caught Massey cutting coal with ventilation curtains rolled up and left out of the way, MSHA said. The curtains help flush away methane and coal dust, which can ignite and cause explosions.

The Sept. 28 inspection is part of an agency crackdown launched after 29 miners died and two suffered serious injuries in an explosion at Massey's Upper Big Branch mine in nearby Raleigh County. The April explosion was the deadliest at a U.S. coal mine since 1970, and it remains the subject of criminal and civil investigations.

"This is a reflection of the problem that we have in this mining industry with some who, regardless of what you do, ignore the mine law," MSHA director Joe Main told The Associated Press. "What we found at Seng Creek, there is absolutely no justification to be operating a mine in this condition."

Massey agreed.

"This situation was very frustrating and totally unacceptable," Massey spokesman Jeff Gillenwater said in an e-mail. "We appreciate MSHA's blitz for uncovering conduct that we did not uncover ourselves."

However, Main said it's up to mine operators to comply with the law.

"There is a problem here. First off it is the mine operator's responsibility to put in place a health and safety management program," Main said. "They went out of the way to engage in the conduct at that mine."

MSHA conducted the Seng Creek inspection after receiving an anonymous tip that Massey was making so-called deep cuts. The practice allows mines to cut larger quantities of coal without pausing to move ventilation equipment and install roof supports. The practice tends to generate more coal dust and requires prior approval from MSHA.

"It's a more productive means," Main said. "They were actually deep cutting and they didn't even take the time to put up the ventilation controls.

"Those things just don't happen, they're orchestrated."

Gillenwater said the president of Elk Run Coal, the subsidiary that operates Seng Creek, had told the mine's superintendent that Massey expects compliance with the law.

"The foreman in charge of the section was told the same thing by his superintendent right before he went underground the day of the violations," Gillenwater said. "This training was simply violated. We will redouble our efforts."

Gillenwater said Massey fired the foreman who allowed mining without ventilation curtain and two miners and suspended nine others for three days.